What stylesheet in a theme controls the colours in the data part of the table in about:performance? I cannot find a stylesheet called aboutPerformance.css, so where are these colours set up? It is not in common.css.

I see that one of these files has this line:@import url("chrome://global/skin/in-content/common.css");I added the variable "--aboutSupport-table-background" to global > in-content > common.css, but it did nothing. What do I have to add to a theme to get the table background to change? Failing that, how would I get the text in the table data to change colour?

After I cleared the cache, the first suggestion worked. I did not have to use the style editor to add that code. All I had to do was extract common.css from the theme .xpi file, add the code to it, then put it back in. Thanks for the solution.

The second block of code produces an error:Exception: TypeError: Components.classes is undefined